Extensible mark-up language (XML) schemas are well known in the art. They allow users to define complex structured XML data objects, which facilitates the wide spread use of the XML format in data storage and processing in databases. As each XML document is offered, they must be validated against its XML schema definition to ensure compliance prior to their use in data storage and processing.
Conventionally, two major approaches to XML schema validation are used. First is a general-purpose schema validation parser. In this approach, the parser receives the XML schema definition and the XML document as input, parses the XML document into a tree format, parses the XML schema definition into a schema tree format, and then traverses the XML document tree to check it against the XML schema tree. The same general-purpose schema validation parser is used for many different XML schemas. Although this approach is flexible in that it can validate against many different XML schemas, this approach typically has poor performance.
A second approach is to generate an XML schema validation parser code based on a particular XML schema definition. The XML schema validation parser code is compiled into executable code, which is used to validate an XML document against the particular XML schema definition. Although this approach can be faster than the first approach, there can be a large number of validation parsers when there are a large number of XML schema definitions, incurring space overhead. It is also inflexible as each XML schema validation parser can only validate against a particular XML schema.
Accordingly, there exists a need for an improved method and system for XML schema validation. The improved method and system should provide high performance without incurring high space overhead. The present invention addresses such a need.